Sniffin’ Sticks to Measure Olfactory Function and Recovery Following Bilateral Superior Turbinate Resection as Part of Endoscopic Transsphenoidal Approach

Abstract

Background:

Extended endoscopic transsphenoidal (EET) approaches can include complete resection of both superior turbinate (ST) for wider exposure. Moreover, ST resection has been associated with postoperative olfactory impairment.

Objective:

We sought to determine the impact of bilateral ST resection on olfaction during a transsphenoidal approach.

Method:

A prospective observational study was conducted on 29 patients undergoing endoscopic skull base surgery sparing the olfactory tracts at a tertiary academic center. Olfactory function was measured with Sniffin’ Sticks at the preoperative visit, 2-weeks and 6 to 8 weeks postoperatively. All components: odor threshold (OT), odor discrimination (OD), odor identification (OI) and composite scores (TDI = OT+OD+OI) were evaluated.

Result:

Study was completed in 15 patients with 14 excluded due to a variety of reasons. At 2 weeks, a significant decrease was noted in composite scores (32.3 ± 5.4 vs. 23.8 ± 5.8, P < .05) and OT (7.7 vs. 3.2, P < .05). There was a significant increase in olfactory scores between post-op weeks 2 and 6 to 8 weeks in TDI (23.8 vs. 31.4, P < .05) as well as in OT (3.2 vs. 7.6, P < .05), OD (9.4 vs. 11.1, P < .05), and OI (11.1 vs. 12.7, P < .05). No significant difference was found between TDI (32.3 ± 5.4 vs. 31.4 ± 5.1), OT (7.7 vs. 7.6), OD (11.4 vs. 11.1) and OI (13.2 vs. 12.7) from preoperative and 6-8 weeks postoperative visits.

Conclusion:

Patients undergoing bilateral ST resection during EET procedures experience transient hyposmia postoperatively. However, the olfactory function normalizes to preoperative levels at 6 to 8 weeks. The resection of the bilateral superior turbinate does not appear to decrease olfactory function.

Keywords

olfaction test miscellaneous olfactory function test endoscopic pituitary surgery nasal turbinate hyposmia endoscopic sinus surgery endoscopic skull base surgery

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